diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning.kshlib b/tests/zfs-tests/tests/functional/block_cloning/block_cloning.kshlib
index 9998e5a87b..8e16366b4c 100644
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning.kshlib
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning.kshlib
@@ -34,13 +34,21 @@ function have_same_content
 	log_must [ "$hash1" = "$hash2" ]
 }
 
-function unique_blocks
+#
+# get_same_blocks dataset1 path/to/file1 dataset2 path/to/file2
+#
+# Returns a space-separated list of the indexes (starting at 0) of the L0
+# blocks that are shared between both files (by first DVA and checksum).
+# Assumes that the two files have the same content, use have_same_content to
+# confirm that.
+#
+function get_same_blocks
 {
 	typeset zdbout=${TMPDIR:-$TEST_BASE_DIR}/zdbout.$$
 	zdb -vvvvv $1 -O $2 | \
-	    awk '/ L0 / { print ++l " " $3 " " $7 }' > $zdbout.a
+	    awk '/ L0 / { print l++ " " $3 " " $7 }' > $zdbout.a
 	zdb -vvvvv $3 -O $4 | \
-	    awk '/ L0 / { print ++l " " $3 " " $7 }' > $zdbout.b
+	    awk '/ L0 / { print l++ " " $3 " " $7 }' > $zdbout.b
 	echo $(sort $zdbout.a $zdbout.b | uniq -d | cut -f1 -d' ')
 }
 
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange.ksh
index 9adcbfcd88..43ea47b0ef 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange.ksh
@@ -54,7 +54,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
-log_must [ "$blocks" = "1 2 3 4" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
+log_must [ "$blocks" = "0 1 2 3" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_cross_dataset.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_cross_dataset.ksh
index 07e089e89c..74e6b04903 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_cross_dataset.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_cross_dataset.ksh
@@ -58,8 +58,8 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/$TESTFS1/file1 /$TESTPOOL/$TESTFS2/file2
 
-typeset blocks=$(unique_blocks \
+typeset blocks=$(get_same_blocks \
   $TESTPOOL/$TESTFS1 file1 $TESTPOOL/$TESTFS2 file2)
-log_must [ "$blocks" = "1 2 3 4" ]
+log_must [ "$blocks" = "0 1 2 3" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback.ksh
index 87f99eb5c0..9a96eacd60 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback.ksh
@@ -58,8 +58,8 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file /$TESTPOOL/clone
 
-typeset blocks=$(unique_blocks $TESTPOOL file $TESTPOOL clone)
-log_must [ "$blocks" = "1 2 3 4" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file $TESTPOOL clone)
+log_must [ "$blocks" = "0 1 2 3" ]
 
 
 log_note "Copying within a block with copy_file_range"
@@ -69,8 +69,8 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file /$TESTPOOL/clone
 
-typeset blocks=$(unique_blocks $TESTPOOL file $TESTPOOL clone)
-log_must [ "$blocks" = "2 3 4" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file $TESTPOOL clone)
+log_must [ "$blocks" = "1 2 3" ]
 
 
 log_note "Copying across a block with copy_file_range"
@@ -80,7 +80,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file /$TESTPOOL/clone
 
-typeset blocks=$(unique_blocks $TESTPOOL file $TESTPOOL clone)
-log_must [ "$blocks" = "2" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file $TESTPOOL clone)
+log_must [ "$blocks" = "1" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback_same_txg.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback_same_txg.ksh
index 3451f887af..a10545bc07 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback_same_txg.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_fallback_same_txg.ksh
@@ -59,7 +59,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file /$TESTPOOL/clone
 
-typeset blocks=$(unique_blocks $TESTPOOL file $TESTPOOL clone)
+typeset blocks=$(get_same_blocks $TESTPOOL file $TESTPOOL clone)
 log_must [ "$blocks" = "" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_partial.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_partial.ksh
index ecac62b203..a5da0a0bd3 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_partial.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_copyfilerange_partial.ksh
@@ -54,7 +54,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
 log_must [ "$blocks" = "" ]
 
 log_must clonefile -f /$TESTPOOL/file1 /$TESTPOOL/file2 131072 131072 262144
@@ -62,7 +62,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
-log_must [ "$blocks" = "2 3" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
+log_must [ "$blocks" = "1 2" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_disabled_copyfilerange.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_disabled_copyfilerange.ksh
index 30b155a140..d21b625113 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_disabled_copyfilerange.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_disabled_copyfilerange.ksh
@@ -54,7 +54,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
 log_must [ "$blocks" = "" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlone.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlone.ksh
index d13a392298..3f227fb68e 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlone.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlone.ksh
@@ -50,7 +50,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
-log_must [ "$blocks" = "1 2 3 4" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
+log_must [ "$blocks" = "0 1 2 3" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange.ksh
index 6556050c43..cefc4336ae 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange.ksh
@@ -50,7 +50,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
-log_must [ "$blocks" = "1 2 3 4" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
+log_must [ "$blocks" = "0 1 2 3" ]
 
 log_pass $claim
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange_partial.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange_partial.ksh
index 37a3511a26..067f55aaa6 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange_partial.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_ficlonerange_partial.ksh
@@ -50,7 +50,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
 log_must [ "$blocks" = "" ]
 
 log_must clonefile -r /$TESTPOOL/file1 /$TESTPOOL/file2 131072 131072 262144
@@ -58,7 +58,7 @@ log_must sync_pool $TESTPOOL
 
 log_must have_same_content /$TESTPOOL/file1 /$TESTPOOL/file2
 
-typeset blocks=$(unique_blocks $TESTPOOL file1 $TESTPOOL file2)
-log_must [ "$blocks" = "2 3" ]
+typeset blocks=$(get_same_blocks $TESTPOOL file1 $TESTPOOL file2)
+log_must [ "$blocks" = "1 2" ]
 
 log_pass $claim